CVE-2026-4881

Improper Permission Checks Allow Server‑Level Configuration Changes via API

Published Jun 4, 2026 CVSS 4.0 · 6 Medium EPSS < 1% KEV · Not listed
Description
In affected versions of Octopus Server, permissions were not checked correctly resulting in any authenticated user being able to make server level changes using a certain API endpoint despite receiving an error.

Analysis

AI-generated

Technical impact

The vulnerability arises from incorrect permission checks in Octopus Server. As a result, any authenticated user can invoke a particular API endpoint to make server‑level changes, even though the system reports an error. This flaw enables modification of configuration that should be restricted to privileged users, potentially compromising the integrity of the deployment environment.

Affected Systems

The affected product is Octopus Deploy Octopus Server. Specific product versions are not provided, so all currently deployed instances of Octopus Server are potentially vulnerable until a patch that restores proper access control is applied. The issue is limited to the server component and does not affect the client or agent.

Risk and Exploitability

The CVSS score of 6.0 indicates moderate severity, and the EPSS score is less than 1%, suggesting a low probability of exploitation. The vulnerability is not listed in the CISA KEV catalog. Based on the description, it is inferred that an attacker must already possess valid credentials to exploit the flaw. Once authenticated, the attacker can manipulate the server using the susceptible API, leading to unintended configuration changes that could compromise system integrity. The exploitation does not require remote code execution, but the impact on system integrity could be significant.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Apply the vendor patch that fixes the permission check on the vulnerable API endpoint.
  • If an update is not immediately possible, restrict the API permissions of non‑admin users to read‑only roles or disable the endpoint until the fix is applied.
  • Monitor and audit API usage logs for unusual activity and enforce network segmentation so that only trusted components can reach the Server API.

Generated by OpenCVE AI on June 4, 2026 at 17:52 UTC.

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Octopus
Octopus octopus Server
Vendors & Products Octopus
Octopus octopus Server
Type Values Removed Values Added
Title Improper Permission Checks Allow Server‑Level Configuration Changes via API
Type Values Removed Values Added
Title Authenticated User Can Perform Server‑Level Changes via API in Octopus Server
Weaknesses CWE-285
Type Values Removed Values Added
Weaknesses CWE-862
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Title Authenticated User Can Perform Server‑Level Changes via API in Octopus Server
Weaknesses CWE-285
Type Values Removed Values Added
Description In affected versions of Octopus Server, permissions were not checked correctly resulting in any authenticated user being able to make server level changes using a certain API endpoint despite receiving an error.
References
Metrics cvssV4_0

{'score': 6, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
Octopus
Published
Updated
Jun 4, 2026, 1:05 PM
Reserved
Mar 26, 2026, 7:19 AM
Status
Analyzed
Published
Jun 4, 2026, 10:16 AM
Modified
Jul 22, 2026, 8:10 PM